Investigations of phase-separated Langmuir-Blodgett films by atomic force microscopy reveal that on a scale of 30 to 200 micrometers, these images resemble those observed by fluorescence microscopy. Fine structures (less than 1 micrometer) within the stearic acid domains were observed, which cannot be seen by conventional optical microscopic techniques. By applying the force modulation technique, it was found that the elastic properties of the domains in the liquid condensed phase and grains observed within the liquid expanded phase were comparable. Small soft residues in the domains could also be detected. The influence of trace amounts of a fluorescence dye on the micromorphology of monolayers could be detected on transferred films.

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The aggregation behavior of the amphiphilic L-glutamate derivatives 1 and 2 and the micromorphology alteration of their domain structures induced by an adjacent mobile polymer matrix have been investigated via fluorescence microscopy at air/water and air/substrate interfaces. The electrostatic interaction of the positively charged lipids 1 and 2 with the polyelectrolyte alginic acid sodium salt in the aqueous subphase leads to a distinct fluidization of the monolayer at the air/water interface. Monolayers have been transferred by the Langmuir-Blodgett (LB) technique out of different aggregation states onto various substrates. The various substrates have been prepared by successive polymer preadsorption to the solid support. This technique of polymer-polymer complexation or polymer stacking permits a modification of the surface constitution and the polymer matrix thickness or swellability. The morphology variability of the domain structures of the amphiphiles 1 and 2 on the solid supports has been investigated by fluorescence microscopy.Due to the adjacent mobile polymer matrix and its water swellability, the supported amphiphilic monolayers were able to change their domain structures. The morphology alteration at the air/substrate interface has been examined intensively as a function of the adjacent polymer layers, the water content, and the temperature. Moreover, reversible temperature dependent domain structure variations of transferred layers have been examined by fluorescence microscopy.

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